Common computer-peripheral input devices include mice, keyboards, trackballs, and the like, where keyboards can be used to directly enter words and characters into a computer, and therefore, draw great attention from users and input device manufacturers.
Referring to FIG. 1, FIG. 1 is a schematic structural diagram of the appearance of a conventional keyboard. A plurality of keys 10 is exposed on a surface of a keyboard 1, and the keys 10 are classified as generic keys 101, number keys 102, function keys 103, and the like. The keys are provided for a user to touch and press with fingers, to generate a corresponding signal input to the computer, to enable the computer to implement a function of the touched and pressed key. For example, the generic keys 101 are used for inputting symbols such as English letters, the number keys 102 are used for inputting numbers, and the function keys 103 are used for providing various functions such as F1 to F12. The conventional keyboard 1 is a keyboard for a notebook computer.
With the evolution of technologies, keyboard manufacturers are devoted to researching and developing various keyboards having particular functions, such as a luminous keyboard, to meet various requirements of different users. An internal structure of a conventional luminous keyboard is described below. Referring to FIG. 2, FIG. 2 is a structural sectional view of a conventional luminous keyboard. A conventional luminous keyboard 2 includes a plurality of keys 20, a membrane switch circuit 21, a light guide plate 22, a light emitting module 23, a support plate 24, and a reflector plate 25. The key 20 includes a key cap 201, a scissors-type connecting element 202, and an elastic element 203. In the conventional luminous keyboard 2, an arrangement sequence of the foregoing components from top to bottom are the key cap 201, the scissors-type connecting element 202, the elastic element 203, the membrane switch circuit 21, the support plate 24, the light guide plate 22, and the reflector plate 25, and the support plate 24 located between the membrane switch circuit 21 and the light guide plate 22 can bear the key cap 201, the scissors-type connecting element 202, the elastic element 203, and the membrane switch circuit 21 thereon.
In the key 20, the key cap 201 is exposed out of the conventional keyboard 2 and can be touched and pressed by a user, the scissors-type connecting element 202 is used for connecting the key cap 201 and the support plate 24, and the elastic element 203 penetrates through the scissors-type connecting element 202 and is in contact with the key cap 201 and the membrane switch circuit 21 separately. The membrane switch circuit 21 includes an upper circuit board 211, an isolation layer 212, and a lower circuit board 213. The upper circuit board 211 has a plurality of upper conductive parts 2111. The isolation layer 212 is located below the upper circuit board 211 and has a plurality of isolation layer holes 2121 corresponding to the plurality of upper conductive parts 2111. The lower circuit board 213 is located below the isolation layer 212 and has a plurality of lower conductive parts 2131 corresponding to the plurality of upper conductive parts 2111, so that the plurality of lower conductive parts 2131 and the plurality of upper conductive parts 2111 form a plurality of key switches 214. The upper circuit board 211, the isolation layer 212, and the lower circuit board 213 are all made of a transparent material, and the transparent material is made from polycarbonate (PC) or polyethylene (PE), to have a light transmission effect.
The light emitting module 23 includes a power supply circuit board 231 and a plurality of light emitting elements 232 (only two are shown). The power supply circuit board 231 is located below the membrane switch circuit 21 and is used for supplying power to the plurality of light emitting elements 232. The plurality of light emitting elements 232 are disposed on the power supply circuit board 231 and extend into a plurality of reflector holes 251 of the reflector plate 25 and a plurality of light guide plate holes 221 of the light guide plate 22. When the plurality of light emitting elements 232 is powered on, the plurality of light emitting elements 232 generates a plurality of beams B, and the plurality of beams B is projected to the light guide plate 22. The light emitting elements 232 are edge-type light-emitting diodes (LEDs). A function of the light guide plate 22 is guiding a plurality of beams B to be projected to the key cap 201. The reflector plate 25 is disposed below the light guide plate 22 and can reflect the plurality of beams B to project the plurality of beams B upward, so as to avoid waste of the beams B. Two side edges 252 of the reflector plate 25 are bent upward and wrap a plurality of side edges 222 of the light guide plate 22, to avoid a light leakage phenomenon on the side edges 222 of the light guide plate 22.
In the conventional luminous keyboard 2, each key cap 201 has an out-light area 2011, and the out-light area 2011 is a position where a letter or a symbol is located. The position of the out-light area 2011 corresponds to the position where a light guide dot 223 is located on the light guide plate 22, so that the beam penetrates through the light guide dot 223 and is guided upward to the out-light area 2011. When the beam B transmitted and guided in the light guide plate 22 is projected to the light guide dot 223, the light guide dot 223 can guide the beam B to be projected upward. The beam B projected upward can sequentially penetrate through support plate holes 241 of the support plate 24 and the membrane switch circuit 21, and further penetrate through the out-light area 2011 of the key cap 201, so that a letter or a symbol on the key cap 201 can transmit light and have a light emitting effect.
Recently, users expect that a light emitting effect of each key in a luminous keyboard can be controlled. For example, a key A is controlled to emit light, but a key B is controlled not to emit light. However, the foregoing conventional luminous keyboard 2 cannot meet the foregoing requirement. To satisfy requirements of users, a direct-type luminous keyboard needs to be used. In the direct-type luminous keyboard, a single direct-type LED is disposed below a key cap of each key, so that a light emitting situation of each direct-type LED can be controlled separately to satisfy the requirements of the users. A beam generated by the direct-type LED is directly projected upward to the corresponding key cap. Therefore, a light projection effect of the direct-type luminous keyboard is excessively concentrated, and a light evenness effect cannot be achieved.
Therefore, a luminous keyboard having a function of separately controlling a light emitting situation of a key and having an even light-emitting effect is needed.